Apparatus for attaching printing plates to a cylinder



Sept. 22, 1936. J J KESSLER 2,055,295

APPARATUS FOR ATTACHING PRINTING PLATES TO A CYLINDER Filed Sept. 1,1933 ZSheets-Sheet 1' Patented Sept. 22, 1936 UNITED STTES APPARATUS FORATTACHING PRINTING PLATES TO A CYLINDER Jack J. Kessler, Cleveland,Ohio, assignor to United Antographic Register 00., Chicago, 111., acorporation of Illinois Application September 1,1933, Serial No. 687,853

2 Claims.

This invention relates to improved means for attaching the rubberprinting plates to a roll of a cylinder press with all of the forms inproper spaced relation.

The invention is illustrated in a preferred embodiment in theaccompanying drawings, in which Fig. 1 is an end elevational view of aprinting cylinder with a rubber printing plate attached in accordancewith the present invention; Fig. 2 is a plan view of a clamping bar usedto grip an end of the printing plate; Fig. 3 is a vertical sectionalview taken as indicated at line 3 of Fig. Fig. 4 is a vertical sectionalview taken as indicated at line 4 of Fig. 5; Fig. 5 is a brokensectional view of a printing roll; Fig. 6 is a plan view of an anchorbar used to attach one end of the printing plate to the printingcylinder; and Fig. '7 is a dove-tail shaped insert for the anchor bar.

As shown in Fig. l the printing cylinder 3| is provided with a groove,or slot, 32 which is angularly disposed with respect to the radius ofthe cylinder. One end of the printing plate is first attached within thegroove, or slot, by means of an anchor bar 33 which is rigidly fastenedto the bottom of the groove, or slot, 32 by means of machine screws 34which extend through countersunk openings 35 in the bar. The anchor baris provided with cut out portions 36 which are beveled downwardly at 31,as shown in Fig. 5, and are adapted to receive dovetail shaped inserts38. As shown in Fig. 6, the insert and anchor bar together form a tappedcountersunk opening 39, forming a sort of split-nut for a machinescrew40. Preferably, the outer side of the insert 38 is provided withserrations as indicated at ii in Fig. 7. One marginal end 28 of thebrass plate E is inserted between the anchor bar assembly and the wallof the slot 32 as shown in Fig. 3. The screws 46 are then tightened upand as there is a differential between the size of the countersink 39 inthe bar and insert, and that of the bevel of the head of the screw til,the insert is spread slightly, not more than .010 inch, and one end ofthe plate is clamped in position.

The opposite end of the printing plate is then gripped by a pair ofclamping bars 53 and M which are drilled and tapped at 55 so that theymay be drawn together by means of screws 35. As shown in Fig. 2 thesebars are equipped with longitudinal slots il through which machinescrews 48 may project and extend down into tapped holes 49 provided inthe anchor bar. The printing cylinder 3i is provided with openings 5|]to permit the screws 48 to extend downwardly therein. It will beunderstood that by this apparatus one end of the printing plate is firstgripped by the inserts 38 and after the plate has been wrapped aroundthe cylinder the other end may be drawn down into position by tighteningthe screws 48. By this means the plate may be stretched and held snuglyon the printing cylinder.

As shown in Figs. 3 and 5, the upper clamping bar is provided withtapped openings 5i which may be engaged by hand-tools 52 to facilitatethe removal of the printing plate from the machine.

No invention is claimed in the present application for the material usedin forming the rubber printing plate nor in the fabric used forcementing the brass backing plate to the rubber printing plate. Theseare articles of manufacture obtainable in the open market.

The foregoing detailed description has been given for clearness ofunderstanding only, and no unnecessary limitations should be understoodtherefrom, but theappended claims should be construed as broadly aspermissible, in view of the prior art.

What I regard as new, and desire to secure by Letters Patent, is:

1. In a machine of the character set forth: a printing cylinder having atransverse slot; and means for wedging a plate within said slotcomprising an anchor bar adapted to be bolted to the cylinder at thebottom of said slot, said anchor bar having dove-tail cut out portions,and dovetail inserts within said cut-out portions forming a split nutwith said anchor bar by providing a tapped countersunk opening for amachine screw adapted to spread the same.

2. In a machine of the character set forth: a printing cylinder having atransverse slot; and means for stretching and securing a flexibleprinting plate to said cylinder comprising an anchor bar bolted to thecylinder within said slot, wedgeblocks within said bar to clamp one endof the plate within said slot, a tail-piece adapted to clamp onto theopposite end of said plate after the plate is wrapped around thecylinder,and screw means for drawing said tail-piece down against theanchor bar.

JACK J. KESSLER.

